• Molecules and Cells
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• 제28권1호
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• pp.1-5
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• 2009

Vascular endothelial growth factor (VEGF) is essential for many angiogenic processes both in normal and pathological conditions. However, the signaling pathways involved in VEGF-induced angiogenesis are incompletely understood. The protein kinase D1 (PKD1), a newly described calcium/calmodulin-dependent serine/threonine kinase, has been implicated in cell migration, proliferation and membrane trafficking. Increasing evidence suggests critical roles for PKD1-mediated signaling pathways in endothelial cells, particularly in the regulation of VEGF-induced angiogenesis. Recent studies show that class IIa histone deacetylases (HDACs) are PKD1 substrates and VEGF signal-responsive repressors of myocyte enhancer factor-2 (MEF2) transcriptional activation in endothelial cells. This review provides a guide to PKD1 signaling pathways and the direct downstream targets of PKD1 in VEGF signaling, and suggests important functions of PKD1 in angiogenesis.

• Mycobiology
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• 제39권4호
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• pp.249-256
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• 2011

Microorganisms are significantly affected when the ambient pH of their environment changes. They must therefore be able to sense and respond to these changes in order to survive. Previous investigators have studied various fungal species to define conserved pH-responsive signaling pathways. One of these pathways, known as the Pal/Rim pathway, is activated in response to alkaline pH signals, ultimately targeting the PacC/Rim101 transcription factor. Although the central signaling components are conserved among divergent filamentous and yeast-like fungi, there is some degree of signaling specificity between fungal species. This specificity exists primarily in the downstream transcriptional targets of this pathway, likely allowing differential adaptation to species-specific environmental niches. In this review, the role of the Pal/Rim pathway in fungal pH response is discussed. Also highlighted are functional differences present in this pathway among human fungal pathogens, differences that allow these specialized microorganisms to survive in the various micro-environments of the infected human host.

• 치위생과학회지
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• 제10권4호
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• pp.227-231
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• 2010

The purpose of this study was to examine the MAPK signaling pathways involved in regulation of HO-1 and the odontoblast differentiation markers during the odontoblastic differentiation for HDPCs. We evaluated cell growth by MTT assay and differentiation marker mRNA expression by RT-PCR. When the cells were treated with p38 inhibitor (SB203580, $10{\mu}M$), JNK inhibitor (SP600125, $10{\mu}M$), and ERK inhibitor (PD98059, $20{\mu}M$) for 7 days, cell growth and expression of HO-1 and differentiation makers were significantly decreased in HDPCs. Our results suggest that odontoblastic differentiation is positively regulated by HO-1 induction in HDPCs via ERK, JNK, and p38 signaling pathways. Thus, pharmacological HO-1 induction might represent a potent therapeutic approach for pulp capping and the regeneration of HDPCs.

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2003년도 Annual Meeting of KSAP : International Symposium on Pharmaceutical and Biomedical Sciences on Obesity
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• pp.83-83
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• 2003

In our previous study, glucose deprivation was reported to induce the potentiated death and ATP loss in immunostimulated astroglia. And this vulnerability to glucose deprivation was due to overproduction of nitric oxide (NO) and hydrogen peroxide (H$_2$O$_2$). In the present study, the role of extracellular signal-regulated kinase 1/2 (ERK1/2) in the glucose deprivation-induced death of immunostimulated astroglia was examined. We showed that immunostimulation with LPS+IFN-ν activated the ERKl/2 signal pathway and produced a large amount of NO and H$_2$O$_2$. Generation of NO and H$_2$O$_2$ in immunostimulated astroglia was mediated via ERK1/2 signal pathways, since addition of the ERK kinase (MEKl) inhibitor PD98059 reduced NO and H$_2$O$_2$production. ERK1/2 activation-mediated NO and H$_2$O$_2$ production is due to an activation of iNOS and NADPH oxidase, respectively. Finally, we found that glucose deprivation caused ATP depletion and the augmented death in immunostimulated astroglia, which was also prevented by PD98059 treatment. These results demonstrate that the ERK1/2 signal pathways play an important role in glucose deprivation induced the death in immunostimulated astroglia by regulating the generation of NO and H$_2$O$_2$.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-1
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• pp.60-61
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• 2003

Human Genome Project has recently been completed and the information on nucleotide sequences of our whole genome is now available at the public or commercial data banks. Next goals are to identify the functions of each gene and to elucidate the intracellular signal transduction pathways regulating gene expression. We have established a PCR-based bioassay to search for biologically active compounds that can modulate the expression of genes encoding important proteins. (omitted)

• 한국식물학회:학술대회논문집
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• 한국식물학회 1996년도 식물학심포지움 식물호르몬과 신호전달
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• pp.10-17
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• 1996

Fern gametophytes are a good model system to study plant morphogenesis, because of their simple organization and various photocontrolled responses. We studied fern photomorphogenesis including chloroplast photoorientation using Adiantum gametophytes to analyze signal transduction pathways of plant photomorphogenesis. Chloroplast photoorientation will be shown in detail and molecular structure of fern phytochromes and blue light absorbing pigments will also be discussed.

• 한국어병학회지
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• 제20권1호
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• pp.71-81
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• 2007

넙치, Paralichthys olivaceus 병어에서 분리된 Photobacterium damselae subsp. damselae와 Vibrio spp.(V. anguillarum, V. splendidus, V. harveyi and V. ordalii)의 병원성을 in vitro에서 조사하였다. Extracellular products (ECPs)의 성상은 효소 활성, 양과 넙치 적혈구에 대한 용혈능과 cell-line에 대한 세포 독성을 조사하였다. 그리고 세균의 internalization에서 signal transduction pathways를 signal transduction inhibitor를 이용하여 조사하였다.P. damselae는 phospholipase 활성, 넙치 적혈구에 대한 용혈능, 세포독성이 높게 나타났으며, 분리된 vibrios 균주에 비하여 internalization에서 다양한 경로를 나타내었다. 따라서 이러한 활성은 P. damselae의 병원성과 관련이 있을 것으로 생각된다.

• Molecules and Cells
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• 제43권6호
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• pp.509-516
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• 2020

To perceive fluctuations in light quality, quantity, and timing, higher plants have evolved diverse photoreceptors including UVR8 (a UV-B photoreceptor), cryptochromes, phototropins, and phytochromes (Phys). In contrast to plants, prokaryotic oxygen-evolving photosynthetic organisms, cyanobacteria, rely mostly on bilin-based photoreceptors, namely, cyanobacterial phytochromes (Cphs) and cyanobacteriochromes (CBCRs), which exhibit structural and functional differences compared with plant Phys. CBCRs comprise varying numbers of light sensing domains with diverse color-tuning mechanisms and signal transmission pathways, allowing cyanobacteria to respond to UV-A, visible, and far-red lights. Recent genomic surveys of filamentous cyanobacteria revealed novel CBCRs with broader chromophore-binding specificity and photocycle protochromicity. Furthermore, a novel Cph lineage has been identified that absorbs blue-violet/yellow-orange light. In this minireview, we briefly discuss the diversity in color sensing and signal transmission mechanisms of Cphs and CBCRs, along with their potential utility in the field of optogenetics.

• Molecules and Cells
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• 제26권5호
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• pp.462-467
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• 2008

TPA is known to cooperate with an activated Ras oncogene in the transformation of rodent fibroblasts, but the biochemical mechanisms responsible for this effect have not been established. In the present study we used c-fos promoter-luciferase constructs as reporters, in transient transfection assays, in NIH3T3 cells to assess the mechanism of this cooperation. We found a marked synergistic interaction between TPA and a transfected v-Ha-ras oncogene in the activation of c-fos promoter and SRE. SRE has binding sites for TCF and SRF. A dominant-negative Ras (ras-N17) inhibited the TPA-Ras synergy by blocking the PKC-MAPK-TCF pathway. Dominant-negative RhoA and Rac1 (but not Cdc42Hs) inhibited the TPA-Ras synergy by blocking the Ras-Rho-SRF signaling pathway. Constitutively active $PKC{\alpha}$ and $PKC{\varepsilon}$ showed synergy with v-Ras. These results suggest that the activation of two distinct pathways such as Ras-Raf-ERK-TCF pathway and Rho-SRF pathway are responsible for the induction of c-fos by TPA and Ras in mitogenic signaling pathways.

• The Korean Journal of Physiology and Pharmacology
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• 제24권1호
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• pp.121-126
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• 2020

The ezrin-radixin-moesin (ERM) proteins are a family of membrane-associated proteins known to play roles in cell-shape determination as well as in signaling pathways. We have previously shown that amphetamine decreases phosphorylation levels of these proteins in the nucleus accumbens (NAcc), an important neuronal substrate mediating rewarding effects of drugs of abuse. In the present study, we further examined what molecular pathways may be involved in this process. By direct microinjection of LY294002, a PI3 kinase inhibitor, or of S9 peptide, a proposed GSK3β activator, into the NAcc core, we found that phosphorylation levels of ERM as well as of GSK3β in this site are simultaneously decreased. These results indicate that ERM proteins are under the regulation of Akt-GSK3β signaling pathway in the NAcc core. The present findings have a significant implication to a novel signal pathway possibly leading to structural plasticity in relation with drug addiction.